Performance Questions

We have just completed a major upgrade from 3.3 to 4.0 and of course we are seeing performance problems with IE, this is fine, to be expected and we know they’ll be resolved. However, we can’t release this to our customers until performance problems are rectified. 2 quick questions that will really really help us out:

1) We are still using the compatibility pack. Will doing a “complete” upgrade without the compat pack show us gains in performance? If so, do you have an idea as to what the performance gains would be?
2) In order to schedule with our customers, support, build-team and developers, do you have an approximate time frame when 4.1 will be released? Even if it’s +/- 3 weeks, that is a big help. Will it be in the next 2 months? Further out than that?
We love the new 4.x architecture, we are using it to take advantage of the great charting abilities you have implemented. The architecture and new features are a dream. The inheritance model, the mixins, the class structure with statics, singletons, it’s just an amazing boon to our architecture and allows us to be much more OOP, more organized and develop not only more clearly but faster! We can’t wait to set aside some time to go 4.x completely and use “required” to make the dependency chain clean and clear. Thanks for such a well thought-out piece of software, you guys are true visionaries.

Thanks very much for the help. We are planning to eventually remove the compat layer, but not yet. We haven't tried 4.1 pr yet, simply because it's not ready for prime time and we don't have the extra cycles to spare to try out.

In terms of the release date for 4.1, can we assume that this is an unknown at the moment? Is there a rough guess? 2011 Q3 or 2012 Q1? Or will it be later? This will help us a lot in terms of our ability to plan the next 4 months of development.